This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This proposal is designed to determine the feasibility, staff effort, patient comfort, and false positive rate of implementing a MRI cardiovascular stress perfusion exam with regadenoson (Lexiscan[unreadable]?[unreadable]) relative to the results obtained during a MRI dobutamine stress wall motion exam. This project will enroll individuals that are scheduled for a dobutamine stress MRI with reactive airways disease (chronic obstructive airway disease or asthma). At our institution this represents 20 [unreadable]?? 25% of patients that are referred for stress testing, or 1 to 2 cases per day. All potential candidates will be contacted in accordance with guidelines approved by the IRB and HIPPA regulatory accords.